Yes, pert near all surviving and current production rimfires qualify as subcalibres.
(Exception being made for the .32, 9mm shot and .41 being produced in very small quantity by Navy Arms, etc.)
CENTERFIRE subcalibres are everything smaller than .22 Hornet, to include .22 Hornet as the borderline round.
Which leads to the following bizarro scenario:
Someone even less sane than TMR necks down a .50 BMG to .20 cal.
It is thusly a subcalibre.
The infra-dinkoidal .25 ACP, which can be used for subcalibre work in cetain varieties of MCA Sports and Alex adaptors...
Is NOT.
(So, iff'n TMR had a darling daughter Eillonwy, and set her up with a T/C in .25-35 with an MCA adaptor to shoot lead bullet loads of .25 Auto until she learned how to hit a squirrel...she would NOT be shooting a genuine subcalibre)
(But: TMR's strapping galoot-like "Ukie" buddy J P Slovjanski could get hold of a Barrett .50, have the custom barrel cranked out for ".20-50 Event Horizon"* and would be zapping varmints at ridiculously high velocities...and going through powder at a phenomenal rate!...with a SUBCALIBER arm!)
*This is MY nickname for such a wildcat. Another possibility would be the .17-50 E=MC2, or the .14-50 Trans-dimensional! LOL!
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Thee Mad Reloader (Moderator--Back in Time, Cowboy Action, Outdoor Cooking, Subcalibers)
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